Oh, my gawd
darkofday - does that mean you work all night long ?
Will have a look at it -

- when I have had some sleep.
BTW - I did something I haven't done before with Calibre.
Gutenberg book UTF-8 text, then search Metadata, ( I also added that info in start of book ) and then run convert to text, after you have selected Kindle format. It DID actually accept text in and text out. Result was actually a pretty perfect layout of the page on Duokan-lite.
I was really pleased by the result. Perhaps I was just lucky with it, but you should try it.
It would be superb if it work with PDF in, text out, but I will have to try that tomorrow.
Just wanted to give you this tip and hope it actually deliver results like I got it. Oh, I turned letter size to minimum on the Kindle.
Hmm.... perhaps you could make your own layout size according to your wanted letter size ?